Chase Utley hit a tying, RBI single off Boone Logan before Howard drove one out to left-center for his fifth career walk-off homer.
Closer La Troy Hawkins (2-1) got the first out in the ninth before Tony Gwynn Jr. reached on second baseman D.J. LeMahieu’s throwing error. Ben Revere followed with a single to right. Jimmy Rollins then hit a foul pop that Troy Tulowitzki, a two-time Gold Glove winning shortstop, dropped for an error. But Hawkins retired Rollins on a liner to left. Logan entered and allowed Utley’s line-drive single to right that scored Gwynn.
Howard then connected on a 2-2 pitch for his ninth homer.
Jonathan Papelbon (1-1) tossed a perfect ninth for the win.